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White House taps Douglas Weaver for NRC role
The Trump White House has nominated seasoned nuclear regulatory expert Douglas Weaver for a commissioner seat on the Nuclear Regulatory Commission. If confirmed, Weaver would fill the seat vacated by NRC commissioner Annie Caputo, who resigned in July.
Weaver’s nomination was sent earlier today to the Senate Environment and Public Works Committee. If confirmed, he would finish the remainder of Caputo’s term, which expires June 30, 2026.
HyeongKae Park, Cassiano R. E. de Oliveira
Nuclear Science and Engineering | Volume 161 | Number 2 | February 2009 | Pages 216-234
Technical Paper | doi.org/10.13182/NSE161-216
Articles are hosted by Taylor and Francis Online.
This paper describes the development of a coupled space-angle a posteriori error analysis and adaptive method for radiation transport calculations based on the second-order, even-parity form of the transport equation discretized by a variational finite element-spherical harmonics method (FE-PN). Rigorous a posteriori error estimates for the global L2 norm in the even-parity angular flux are derived by utilizing duality arguments. Separate error components for the spatial and angular discretizations are obtained by the adaptive algorithm by first seeking convergence in the spatial variable and then by projecting the spatially converged solution onto the higher-order PN equation to estimate the angular truncation error. The validity of the developed coupled space-angle adaptive refinement strategy is assessed by comparing the developed error indicator with the true error for representative problems in one and two dimensions. The method of manufactured solutions and alternative transport solution methods are used to provide the true error. Comparisons indicate that the space-angle adaptivity framework is capable of guiding the FE-PN method toward the true solution.
